aboutsummaryrefslogtreecommitdiffstats
path: root/contrib/libs/llvm14/lib/Target/AArch64/AArch64MCInstLower.cpp
blob: 450c270fcc9b5c7d28f219b5d863f68b1e6f9ac1 (plain) (blame)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
//==-- AArch64MCInstLower.cpp - Convert AArch64 MachineInstr to an MCInst --==//
//
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
// See https://llvm.org/LICENSE.txt for license information.
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
//
//===----------------------------------------------------------------------===//
//
// This file contains code to lower AArch64 MachineInstrs to their corresponding
// MCInst records.
//
//===----------------------------------------------------------------------===//

#include "AArch64MCInstLower.h"
#include "MCTargetDesc/AArch64MCExpr.h"
#include "Utils/AArch64BaseInfo.h"
#include "llvm/CodeGen/AsmPrinter.h"
#include "llvm/CodeGen/MachineBasicBlock.h"
#include "llvm/CodeGen/MachineInstr.h"
#include "llvm/CodeGen/MachineModuleInfoImpls.h"
#include "llvm/IR/Mangler.h"
#include "llvm/MC/MCContext.h"
#include "llvm/MC/MCExpr.h"
#include "llvm/MC/MCInst.h"
#include "llvm/Support/CodeGen.h"
#include "llvm/Support/CommandLine.h"
#include "llvm/Target/TargetLoweringObjectFile.h"
#include "llvm/Target/TargetMachine.h"
using namespace llvm;

extern cl::opt<bool> EnableAArch64ELFLocalDynamicTLSGeneration;

AArch64MCInstLower::AArch64MCInstLower(MCContext &ctx, AsmPrinter &printer)
    : Ctx(ctx), Printer(printer) {}

MCSymbol *
AArch64MCInstLower::GetGlobalAddressSymbol(const MachineOperand &MO) const {
  const GlobalValue *GV = MO.getGlobal();
  unsigned TargetFlags = MO.getTargetFlags();
  const Triple &TheTriple = Printer.TM.getTargetTriple();
  if (!TheTriple.isOSBinFormatCOFF())
    return Printer.getSymbolPreferLocal(*GV);

  assert(TheTriple.isOSWindows() &&
         "Windows is the only supported COFF target");

  bool IsIndirect = (TargetFlags & (AArch64II::MO_DLLIMPORT | AArch64II::MO_COFFSTUB));
  if (!IsIndirect)
    return Printer.getSymbol(GV);

  SmallString<128> Name;
  if (TargetFlags & AArch64II::MO_DLLIMPORT)
    Name = "__imp_";
  else if (TargetFlags & AArch64II::MO_COFFSTUB)
    Name = ".refptr.";
  Printer.TM.getNameWithPrefix(Name, GV,
                               Printer.getObjFileLowering().getMangler());

  MCSymbol *MCSym = Ctx.getOrCreateSymbol(Name);

  if (TargetFlags & AArch64II::MO_COFFSTUB) {
    MachineModuleInfoCOFF &MMICOFF =
        Printer.MMI->getObjFileInfo<MachineModuleInfoCOFF>();
    MachineModuleInfoImpl::StubValueTy &StubSym =
        MMICOFF.getGVStubEntry(MCSym);

    if (!StubSym.getPointer())
      StubSym = MachineModuleInfoImpl::StubValueTy(Printer.getSymbol(GV), true);
  }

  return MCSym;
}

MCSymbol *
AArch64MCInstLower::GetExternalSymbolSymbol(const MachineOperand &MO) const {
  return Printer.GetExternalSymbolSymbol(MO.getSymbolName());
}

MCOperand AArch64MCInstLower::lowerSymbolOperandDarwin(const MachineOperand &MO,
                                                       MCSymbol *Sym) const {
  // FIXME: We would like an efficient form for this, so we don't have to do a
  // lot of extra uniquing.
  MCSymbolRefExpr::VariantKind RefKind = MCSymbolRefExpr::VK_None;
  if ((MO.getTargetFlags() & AArch64II::MO_GOT) != 0) {
    if ((MO.getTargetFlags() & AArch64II::MO_FRAGMENT) == AArch64II::MO_PAGE)
      RefKind = MCSymbolRefExpr::VK_GOTPAGE;
    else if ((MO.getTargetFlags() & AArch64II::MO_FRAGMENT) ==
             AArch64II::MO_PAGEOFF)
      RefKind = MCSymbolRefExpr::VK_GOTPAGEOFF;
    else
      llvm_unreachable("Unexpected target flags with MO_GOT on GV operand");
  } else if ((MO.getTargetFlags() & AArch64II::MO_TLS) != 0) {
    if ((MO.getTargetFlags() & AArch64II::MO_FRAGMENT) == AArch64II::MO_PAGE)
      RefKind = MCSymbolRefExpr::VK_TLVPPAGE;
    else if ((MO.getTargetFlags() & AArch64II::MO_FRAGMENT) ==
             AArch64II::MO_PAGEOFF)
      RefKind = MCSymbolRefExpr::VK_TLVPPAGEOFF;
    else
      llvm_unreachable("Unexpected target flags with MO_TLS on GV operand");
  } else {
    if ((MO.getTargetFlags() & AArch64II::MO_FRAGMENT) == AArch64II::MO_PAGE)
      RefKind = MCSymbolRefExpr::VK_PAGE;
    else if ((MO.getTargetFlags() & AArch64II::MO_FRAGMENT) ==
             AArch64II::MO_PAGEOFF)
      RefKind = MCSymbolRefExpr::VK_PAGEOFF;
  }
  const MCExpr *Expr = MCSymbolRefExpr::create(Sym, RefKind, Ctx);
  if (!MO.isJTI() && MO.getOffset())
    Expr = MCBinaryExpr::createAdd(
        Expr, MCConstantExpr::create(MO.getOffset(), Ctx), Ctx);
  return MCOperand::createExpr(Expr);
}

MCOperand AArch64MCInstLower::lowerSymbolOperandELF(const MachineOperand &MO,
                                                    MCSymbol *Sym) const {
  uint32_t RefFlags = 0;

  if (MO.getTargetFlags() & AArch64II::MO_GOT)
    RefFlags |= AArch64MCExpr::VK_GOT;
  else if (MO.getTargetFlags() & AArch64II::MO_TLS) {
    TLSModel::Model Model;
    if (MO.isGlobal()) {
      const GlobalValue *GV = MO.getGlobal();
      Model = Printer.TM.getTLSModel(GV);
      if (!EnableAArch64ELFLocalDynamicTLSGeneration &&
          Model == TLSModel::LocalDynamic)
        Model = TLSModel::GeneralDynamic;

    } else {
      assert(MO.isSymbol() &&
             StringRef(MO.getSymbolName()) == "_TLS_MODULE_BASE_" &&
             "unexpected external TLS symbol");
      // The general dynamic access sequence is used to get the
      // address of _TLS_MODULE_BASE_.
      Model = TLSModel::GeneralDynamic;
    }
    switch (Model) {
    case TLSModel::InitialExec:
      RefFlags |= AArch64MCExpr::VK_GOTTPREL;
      break;
    case TLSModel::LocalExec:
      RefFlags |= AArch64MCExpr::VK_TPREL;
      break;
    case TLSModel::LocalDynamic:
      RefFlags |= AArch64MCExpr::VK_DTPREL;
      break;
    case TLSModel::GeneralDynamic:
      RefFlags |= AArch64MCExpr::VK_TLSDESC;
      break;
    }
  } else if (MO.getTargetFlags() & AArch64II::MO_PREL) {
    RefFlags |= AArch64MCExpr::VK_PREL;
  } else {
    // No modifier means this is a generic reference, classified as absolute for
    // the cases where it matters (:abs_g0: etc).
    RefFlags |= AArch64MCExpr::VK_ABS;
  }

  if ((MO.getTargetFlags() & AArch64II::MO_FRAGMENT) == AArch64II::MO_PAGE)
    RefFlags |= AArch64MCExpr::VK_PAGE;
  else if ((MO.getTargetFlags() & AArch64II::MO_FRAGMENT) ==
           AArch64II::MO_PAGEOFF)
    RefFlags |= AArch64MCExpr::VK_PAGEOFF;
  else if ((MO.getTargetFlags() & AArch64II::MO_FRAGMENT) == AArch64II::MO_G3)
    RefFlags |= AArch64MCExpr::VK_G3;
  else if ((MO.getTargetFlags() & AArch64II::MO_FRAGMENT) == AArch64II::MO_G2)
    RefFlags |= AArch64MCExpr::VK_G2;
  else if ((MO.getTargetFlags() & AArch64II::MO_FRAGMENT) == AArch64II::MO_G1)
    RefFlags |= AArch64MCExpr::VK_G1;
  else if ((MO.getTargetFlags() & AArch64II::MO_FRAGMENT) == AArch64II::MO_G0)
    RefFlags |= AArch64MCExpr::VK_G0;
  else if ((MO.getTargetFlags() & AArch64II::MO_FRAGMENT) == AArch64II::MO_HI12)
    RefFlags |= AArch64MCExpr::VK_HI12;

  if (MO.getTargetFlags() & AArch64II::MO_NC)
    RefFlags |= AArch64MCExpr::VK_NC;

  const MCExpr *Expr =
      MCSymbolRefExpr::create(Sym, MCSymbolRefExpr::VK_None, Ctx);
  if (!MO.isJTI() && MO.getOffset())
    Expr = MCBinaryExpr::createAdd(
        Expr, MCConstantExpr::create(MO.getOffset(), Ctx), Ctx);

  AArch64MCExpr::VariantKind RefKind;
  RefKind = static_cast<AArch64MCExpr::VariantKind>(RefFlags);
  Expr = AArch64MCExpr::create(Expr, RefKind, Ctx);

  return MCOperand::createExpr(Expr);
}

MCOperand AArch64MCInstLower::lowerSymbolOperandCOFF(const MachineOperand &MO,
                                                     MCSymbol *Sym) const {
  uint32_t RefFlags = 0;

  if (MO.getTargetFlags() & AArch64II::MO_TLS) {
    if ((MO.getTargetFlags() & AArch64II::MO_FRAGMENT) == AArch64II::MO_PAGEOFF)
      RefFlags |= AArch64MCExpr::VK_SECREL_LO12;
    else if ((MO.getTargetFlags() & AArch64II::MO_FRAGMENT) ==
             AArch64II::MO_HI12)
      RefFlags |= AArch64MCExpr::VK_SECREL_HI12;

  } else if (MO.getTargetFlags() & AArch64II::MO_S) {
    RefFlags |= AArch64MCExpr::VK_SABS;
  } else {
    RefFlags |= AArch64MCExpr::VK_ABS;

    if ((MO.getTargetFlags() & AArch64II::MO_FRAGMENT) == AArch64II::MO_PAGE)
      RefFlags |= AArch64MCExpr::VK_PAGE;
    else if ((MO.getTargetFlags() & AArch64II::MO_FRAGMENT) ==
             AArch64II::MO_PAGEOFF)
      RefFlags |= AArch64MCExpr::VK_PAGEOFF | AArch64MCExpr::VK_NC;
  }

  if ((MO.getTargetFlags() & AArch64II::MO_FRAGMENT) == AArch64II::MO_G3)
    RefFlags |= AArch64MCExpr::VK_G3;
  else if ((MO.getTargetFlags() & AArch64II::MO_FRAGMENT) == AArch64II::MO_G2)
    RefFlags |= AArch64MCExpr::VK_G2;
  else if ((MO.getTargetFlags() & AArch64II::MO_FRAGMENT) == AArch64II::MO_G1)
    RefFlags |= AArch64MCExpr::VK_G1;
  else if ((MO.getTargetFlags() & AArch64II::MO_FRAGMENT) == AArch64II::MO_G0)
    RefFlags |= AArch64MCExpr::VK_G0;

  // FIXME: Currently we only set VK_NC for MO_G3/MO_G2/MO_G1/MO_G0. This is
  // because setting VK_NC for others would mean setting their respective
  // RefFlags correctly.  We should do this in a separate patch.
  if (MO.getTargetFlags() & AArch64II::MO_NC) {
    auto MOFrag = (MO.getTargetFlags() & AArch64II::MO_FRAGMENT);
    if (MOFrag == AArch64II::MO_G3 || MOFrag == AArch64II::MO_G2 ||
        MOFrag == AArch64II::MO_G1 || MOFrag == AArch64II::MO_G0)
      RefFlags |= AArch64MCExpr::VK_NC;
  }

  const MCExpr *Expr =
      MCSymbolRefExpr::create(Sym, MCSymbolRefExpr::VK_None, Ctx);
  if (!MO.isJTI() && MO.getOffset())
    Expr = MCBinaryExpr::createAdd(
        Expr, MCConstantExpr::create(MO.getOffset(), Ctx), Ctx);

  auto RefKind = static_cast<AArch64MCExpr::VariantKind>(RefFlags);
  assert(RefKind != AArch64MCExpr::VK_INVALID &&
         "Invalid relocation requested");
  Expr = AArch64MCExpr::create(Expr, RefKind, Ctx);

  return MCOperand::createExpr(Expr);
}

MCOperand AArch64MCInstLower::LowerSymbolOperand(const MachineOperand &MO,
                                                 MCSymbol *Sym) const {
  if (Printer.TM.getTargetTriple().isOSDarwin())
    return lowerSymbolOperandDarwin(MO, Sym);
  if (Printer.TM.getTargetTriple().isOSBinFormatCOFF())
    return lowerSymbolOperandCOFF(MO, Sym);

  assert(Printer.TM.getTargetTriple().isOSBinFormatELF() && "Invalid target");
  return lowerSymbolOperandELF(MO, Sym);
}

bool AArch64MCInstLower::lowerOperand(const MachineOperand &MO,
                                      MCOperand &MCOp) const {
  switch (MO.getType()) {
  default:
    llvm_unreachable("unknown operand type");
  case MachineOperand::MO_Register:
    // Ignore all implicit register operands.
    if (MO.isImplicit())
      return false;
    MCOp = MCOperand::createReg(MO.getReg());
    break;
  case MachineOperand::MO_RegisterMask:
    // Regmasks are like implicit defs.
    return false;
  case MachineOperand::MO_Immediate:
    MCOp = MCOperand::createImm(MO.getImm());
    break;
  case MachineOperand::MO_MachineBasicBlock:
    MCOp = MCOperand::createExpr(
        MCSymbolRefExpr::create(MO.getMBB()->getSymbol(), Ctx));
    break;
  case MachineOperand::MO_GlobalAddress:
    MCOp = LowerSymbolOperand(MO, GetGlobalAddressSymbol(MO));
    break;
  case MachineOperand::MO_ExternalSymbol:
    MCOp = LowerSymbolOperand(MO, GetExternalSymbolSymbol(MO));
    break;
  case MachineOperand::MO_MCSymbol:
    MCOp = LowerSymbolOperand(MO, MO.getMCSymbol());
    break;
  case MachineOperand::MO_JumpTableIndex:
    MCOp = LowerSymbolOperand(MO, Printer.GetJTISymbol(MO.getIndex()));
    break;
  case MachineOperand::MO_ConstantPoolIndex:
    MCOp = LowerSymbolOperand(MO, Printer.GetCPISymbol(MO.getIndex()));
    break;
  case MachineOperand::MO_BlockAddress:
    MCOp = LowerSymbolOperand(
        MO, Printer.GetBlockAddressSymbol(MO.getBlockAddress()));
    break;
  }
  return true;
}

void AArch64MCInstLower::Lower(const MachineInstr *MI, MCInst &OutMI) const {
  OutMI.setOpcode(MI->getOpcode());

  for (const MachineOperand &MO : MI->operands()) {
    MCOperand MCOp;
    if (lowerOperand(MO, MCOp))
      OutMI.addOperand(MCOp);
  }

  switch (OutMI.getOpcode()) {
  case AArch64::CATCHRET:
    OutMI = MCInst();
    OutMI.setOpcode(AArch64::RET);
    OutMI.addOperand(MCOperand::createReg(AArch64::LR));
    break;
  case AArch64::CLEANUPRET:
    OutMI = MCInst();
    OutMI.setOpcode(AArch64::RET);
    OutMI.addOperand(MCOperand::createReg(AArch64::LR));
    break;
  }
}